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Tanogashira Formation (Chiji, 1955) Nagamori et al., 2003

Invalid synonym: Kosenzawa Formation, Sanagura Formation, Sumomodaira Formation, Hiratokosawa Formation, Azumezawa Formation

• Type locality: Tanogashira, Kinasa, Nagano city, Nagano prefecture
• Coherent formation
• Pliocene
• Correlation: Takafu Formation
• Intruded by: Basalt sills, Diorite Porphyry 2

• Lithofacies (Upper): Andesite tuffaceous sandstone
• Lithofacies: Mudstone, Mudstone-dominant interbedded sandstone and mudstone
• Lithofacies (Minor): Conglomerate, Felsic tuff, Scoriaceous tuff, Glendonite

• Thickness: ca. 220 - 1,200 m
• Upper limit: Interfingered (Togakushiyama Formation), Conformity , partly interfingered (Hikage Formaiton), Conformity (Sarumaru Formation), Unconformity (Sasagamine Formation)
• Lower limit: Ichinosaka Tuff
• Lower limit: Conformity (Ronji Formation, Yanagisawa Formation, Idoirisawa Member), Abut unconformity (Togakushiyama Formation)

------ Conformity, ~~~~~~ Unconformity, ~~~--- Local unconformity, '''/,, Interfingered, :::::: Fault, /--/-- Thrust, +__+__ Ground surface, ?--?-- Unknown

• Distribution: Tanogashira - Oshikiri - Ochiai - Tsuchikura - Okususobana park - Karakisawa creek - Kosadezawa creek, Kinasa, Nagano city, Nagano pref.; Mount Gojizo - Mount Sadoyama, Nagano city, Nagano pref.; Nigori river - Niguro river, Nagano city, Nagano pref.; Kataoka, Miasa, Omachi city, Nagano pref.; Kataoka, Miasa, Omachi city, Nagano pref.: Higashisumomoyama, Ogawa city, Kamiminochi county, Nagano pref.
• Fossils: Vertebrata, Crabs (Cancer sp.). Echinoids, Foraminifera, Trace fossils
• Fossils (Shellfishes): Acila sp., Anadara amicula, Buccinidae gen. et sp. indet, Chlamys foeda, Conchocele sp., Lucinoma sp., Mizuhopecten cf. tryblium, Modiolus sp., Panomya cf. beringiana, Serripes sp., Turritella saishuensis motidukii
• Tephra: Hkg10, Ichinosaka Tuff

• Nagamori et al. (2003) Geology of the Togakushi District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, AIST, 109p. (in Japanese with English abstract 3p.)
• Nakano et al. (2002) Geology of the Shiroumadake District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, AIST, 105p. (in Japanese with English abstract 5p.)
• Kato et al. (1989) Geology of the Omachi District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 111p. (in Japanese with English abstract 7p.)